# CVE-2017-9803: Apache Solr Kerberos delegation token functionality flaws

> Attackers can escalate privileges and access or modify private data in Apache Solr clusters when Kerberos delegation tokens are enabled with specific ACL providers.

- **Severity:** High 7.5 (`CVSS:3.0/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 18 Sep 2017
- **Updated:** 17 Sep 2024
- **Also known as:** GHSA-f553-j2gv-g5r9

## What is CVE-2017-9803?

CVE-2017-9803 is a high-severity vulnerability in Apache Solr, published on 18 Sep 2017. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

Apache Solr's Kerberos plugin can be configured to use delegation tokens, which allows an application to reuse the authentication of an end-user or another application. There are two issues with this functionality (when using SecurityAwareZkACLProvider type of ACL provider e.g. SaslZkACLProvider). Firstly, access to the security configuration can be leaked to users other than the solr super user. Secondly, malicious users can exploit this leaked configuration for privilege escalation to further expose/modify private data and/or disrupt operations in the Solr cluster. The vulnerability is fixed from Apache Solr 6.6.1 onwards.

Weakness: CWE-287 (Improper Authentication)

## Which versions are affected by CVE-2017-9803?

2 open source packages ship an affected version, including org.apache.solr:solr-core. It affects 1 product.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `org.apache.solr:solr-core` | Maven | From 6.2.0 | 6.6.1 |
| `org.apache.solr:solr-core` | Maven | From 6.2.0 | 6.6.1 |

Products: Apache Solr.

## How do I fix CVE-2017-9803?

Upgrade org.apache.solr:solr-core to 6.6.1 or later.

## Is CVE-2017-9803 being exploited?

There is no known exploitation of CVE-2017-9803 in the wild and no public exploit code.

## Other vulnerabilities in Apache Solr

- [CVE-2019-17558](https://insights.sbomify.com/CVE-2019-17558/): Apache Solr VelocityResponseWriter Plug-In Remote Code Execution (high 7.5, exploited in the wild)
- [CVE-2019-0193](https://insights.sbomify.com/CVE-2019-0193/): Apache Solr DataImportHandler Code Injection (high 7.2, exploited in the wild)
- [CVE-2024-45216](https://insights.sbomify.com/CVE-2024-45216/): Apache Solr: Authentication bypass possible using a fake URL Path ending (critical 9.8)
- [CVE-2021-44548](https://insights.sbomify.com/CVE-2021-44548/): Apache Solr information disclosure vulnerability through DataImportHandler (critical 9.8)
- [CVE-2021-27905](https://insights.sbomify.com/CVE-2021-27905/): SSRF vulnerability with the Replication handler (critical 9.8)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2017-9803 and fix it if it is affected.

What it is: CVE-2017-9803 is a high-severity vulnerability in Apache Solr, published on 18 Sep 2017. Any signed-in user can exploit it over the network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2017-9803 in the wild and no public exploit code.

Affected packages and fixed versions:
- org.apache.solr:solr-core (Maven): affected from 6.2.0; fixed in 6.6.1
- org.apache.solr:solr-core (Maven): affected from 6.2.0; fixed in 6.6.1

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2017-9803/ (Markdown: https://insights.sbomify.com/CVE-2017-9803/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2017-9803
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2017-9803
- OSV: https://osv.dev/vulnerability/CVE-2017-9803

---
From sbomify Insights: https://insights.sbomify.com/CVE-2017-9803/
Summaries are generated and may contain mistakes; the official description above is the record.